This print for content only-size & color not accurate 7" X 9-1/4" / casebound / malloy

// Invoke stored proc and print out the petname.

carsDB.GetPetName(carID, ref petName);

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8849CH24.qxd  10/19/07  10:11 AM  Page 852

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Console.WriteLine("Car ID {0} has the petname: {1}",

carID, petName);

}

}

Notice that LINQ to SQL completely hides the underlying stored procedure logic from view.

Here, we have no need to manually create a SqlCommand object, fill the parameters collection, or call

ExecuteNonQuery(). Instead, we simply invoke the GetPetName() method of our DataContext-derived

type. Do note, however, that output parameters are represented as reference parameters, and there-

fore must be called using the C# ref keyword.

Now assume we have a second helper function (also called from within Main()) named

PrintOrderForCustomer(). This method will print out some order details for the specified customer

as well as the first and last name of the customer:

static void PrintOrderForCustomer(AutoLot carsDB)

{

int custID = 0;

Console.Write("Enter customer ID: ");

custID = int.Parse(Console.ReadLine());

var customerOrders =

from cust in carsDB.Customers

from o in cust.Orders

where cust.CustID == custID

select new { cust, o };

Console.WriteLine("***** Order Info for Customer ID: {0}. *****", custID);

foreach (var q in customerOrders)

{

Console.WriteLine("{0} {1} is order ID # {2}.",

q.cust.FirstName.Trim(),

q.cust.LastName.Trim(),

q.o.OrderID);

Console.WriteLine("{0} bought Car ID # {1}.",

q.cust.FirstName.Trim(), q.o.CarID);

}

}

Figure 24-5 shows the output when querying about the customer assigned the ID of 1.